[llvm] [CodeGen] Avoid repeated hash lookups (NFC) (PR #131551)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/131551

None

>From 4ce37fa6351d7ee697426e8efc290363d800d688 Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Sun, 16 Mar 2025 09:34:30 -0700
Subject: [PATCH] [CodeGen] Avoid repeated hash lookups (NFC)

---
 llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp b/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp
index 2bd3211d33304..272749f5574c6 100644
--- a/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp
+++ b/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp
@@ -2612,13 +2612,13 @@ removeRedundantDbgLocsUsingForwardScan(const BasicBlock *BB,
         NumDefsScanned++;
         DebugVariable Key(FnVarLocs.getVariable(Loc.VariableID).getVariable(),
                           std::nullopt, Loc.DL.getInlinedAt());
-        auto VMI = VariableMap.find(Key);
+        auto [VMI, Inserted] = VariableMap.try_emplace(Key);
 
         // Update the map if we found a new value/expression describing the
         // variable, or if the variable wasn't mapped already.
-        if (VMI == VariableMap.end() || VMI->second.first != Loc.Values ||
+        if (Inserted || VMI->second.first != Loc.Values ||
             VMI->second.second != Loc.Expr) {
-          VariableMap[Key] = {Loc.Values, Loc.Expr};
+          VMI->second = {Loc.Values, Loc.Expr};
           NewDefs.push_back(Loc);
           continue;
         }